题目内容：

    What were you like as a teenager? I was a nightmare. I was rude to my parents, always stayed out late, never did my homework, hung out with the wrong people and made lots of bad decisions. Apparently, this is the age when teenagers are out of control and behave badly. Maybe，if you’re a teenager now, you think this is unfair criticism or it’s not your fault. Well, you might be right!

Experts have found that it’s a teenager’s brain that is to blame. Between the ages of approximately 13 to 19—a period known as adolescence—the brain is still developing in areas that control behavior. This has an influence on learning and multitasking(同时做多件事情), stress and memory, sleep, addiction, and decision-making. For parents, these consequences often manifest themselves in a variety of behaviors that they may have previously blamed on hormones or just moodiness(喜怒无常).

This is quite a new discovery, according to Professor Sarah-Jayne Blakemore, who, speaking on the BBC radio program The Life Scientific, says, “when I was at university, the dogma(教条) in the text books was that the vast majority of brain development goes on in the first few years of life and nothing much changes after mid-childhood. That dogma is completely false.”

According to Professor Sarah-Jayne Blakemore, students’ not being able to get their homework done on time has something to do with our prefrontal cortex—that’s the part of our brain right at the front, just behind the forehead. She says, “it’s involved in a whole range of very high-level cognitive(认知的) tasks such as decision making and planning—we know that this region is undergoing very large amounts of development during the adolescent years.” This is the part of the brain, mainly involved in planning, and, for a teenager, this hasn’t developed yet. So getting organized to do their homework, for example, can come as a bit of a challenge.

I wish I’d known about this because instead of telling my teacher I’d left my homework on the bus or that the dog had eaten it. Now I could say, “Sorry sir, my brain isn’t developed enough for the cognitive task of planning my homework.”

1.What is the main idea of the text?

A. The growing pains of teenagers.

B. The dogma in the text hooks was false.

C. A new discovery about the teenager’s brain.

D. The students’ new challenge of doing their homework.

2.According to the author, why is it a bit of challenge for students to do their homework?

A. The students are moody.

B. Hormones are to blame.

C. There is too much homework.

D. The brains of the students haven’t been developed.

3.What does the underlined word manifest mean?

A. Develop. B. Show.

C. Abandon. D. Experience.

4.What can we know from the text?

A. The vast majority of brain doesn’t develop after mid-childhood.

B. All of the students are nightmares for parents during adolescence.

C. Prefrontal cortex is undergoing large amounts of development during childhood.

D. The prefrontal cortex has something to do with many high-level cognitive tasks.